I swam in a volcanic hot pool in Fiji and it was incredibly relaxing

On Fiji's second largest island, Vanua Levu, there are volcanic hot pools perfect for swimming in.

The muddy baths are perfect for relaxing in and meeting locals.

To get to the pool, fly into Savusavu and contact Naveria Heights Lodge and ask for a guide.

The island nation of Fiji conjures images of clear bottled water and SCUBA diving to most travelers. But there's another side of this tropical paradise that some don't see. Hidden amongst tribal villages, natural hot springs lap over the veins of a volcano. And they're virtually free to access if you know where to look.

Savusavu airport is a barely-visible strip of tarmac peering out from the jungle of Fiji's second largest island, Vanua Levu. It's the primary entry point for travelers headed for the tropical island's world-class surfing and diving, as well as the smattering of resorts strewn across its beaches.

Its waters are perpetually steaming, a hint at what lies in the jungle. Joe Sills

In town, the island's primary ribbon of asphalt — the Hibiscus Highway — cuts a line past a bustling market, half a dozen Indian restaurants, a yacht club whose ritz lies only in name, and a peculiar stream trickling down from the mountains above: Savusavu locals sometimes cook in the boiling natural waters that course through their town. Noodles, chicken, and as one man said, "pretty much anything," can be found boiling in the Earth. But outside of town, the water is cool enough for people to take a swim.

For generations, Fijians have been swimming in the cool volcanic waters

Slippery. That's the first word that comes to mind. Joe Sills

And on a humid stretch of highway on the outskirts of town, I take the plunge to see what a bath in a volcanic hot pool is like.

Slippery. That's the first word that comes to mind. Naveria Heights Lodge, an Airbnb perched on a peak above Savusavu Bay, has kindly supplied an adventure guide for the day, and as we both scurry down the grassy slope between the highway and one of Vanua Levu's hot pools, we're both trying not to slip. The trail is muddy and well-worn.

At the base of the short trail, a lone man soaks in geothermal heat. The Fijian hot pool is less Roman bath and more farm pond — just a large hole in the ground, lined by coconut trees and a few logs that serve as seats. We slip in, and I get a lesson on how things work: Here, it's all about the mud.

One of the best ways to absorb the volcanic heat is to find a depression in the pool's soft, muddy bottom.

Smoke some suki, a local, dry tobacco free of nicotine and hand-rolled tightly into a bed of newspaper clippings. Joe Sills

You won't be able to see it, but you can feel it. There, you can sink chest deep in the heat, and by digging a little more, you can release even more warmth into the water. It's safe, I'm told. And it's one of the traditional ways to relax here.

Another way? Smoke some suki, a local, dry tobacco free of nicotine and hand-rolled tightly into a bed of newspaper clippings. You can find suki in the town market, or try to bum a smoke at the pools like me.

"How often do you come here?" I ask the local man, who offers a toke of his smoke. He looks into the trees, carefully considering his answer. "Three or four times a day. I walk here from the village. It's not far away."

For an hour or so, our band of travelers soaks in the Earth's warmth, occasionally dipping further into the mud. It's an unlikely band: two Americans, a Fijian villager, and our guide, who lives in town.

Together, we decide there's no better place to be than here.

Getting to Fiji's volcanic hot pools is rather easy

The best way to get to the destination is to fly into Savusava. Joe Sills

Savusavu is less than one hour by air from Fiji's international airport at Nadi. Overnight flights from Los Angeles run daily for around $900. This particular hot pool is a local secret. To get there, contact Naveria Heights Lodge and ask for a guide. Alternately, you can get a glimpse of the boiling springs in Savusavu town without a guide.

Savusavu Bay is also home to some of the best SCUBA diving in the South Pacific, and you won't find a better guide than the team at Jean-Michel Cousteau Resort, just west of town. They offer classes for beginners and overnight expeditions for pros. The dive school there is run by the Cousteau family dive master, who offers up expertise by the pint.

You won’t find a better guide than the team at Jean-Michel Cousteau Resort. Joe Sills

When hunger calls, try the Country Kitchen in Savusavu town. Brews can be found at the local yacht club—check around back.